Drug-eluting angioplasty balloon no advantage in primary PCI

NEW YORK (Reuters Health) – In patients with ST-segment elevation MI undergoing percutaneous coronary intervention, dilatation with the DIOR drug-eluting balloon (DEB) before implantation of a bare metal stent does not improve outcomes.

That’s according to the results of the DEB-AMI trial, scheduled for publication in the June 19/26 issue of the Journal of the American College of Cardiology and available online now. The authors conclude, “We were not able to demonstrate a beneficial effect of pre-treatment with DEB in STEMI.”

Dr. Pieter R. Stella, at the University Medical Center Utrecht, the Netherlands, and colleagues note that there are concerns about the long-term safety of drug-eluting stents (DES) in the STEMI setting, because of local inflammation induced by polymers and drug-related delays in endothelial healing. A drug-eluting balloon “could provide a valid alternative treatment in STEMI patients,” they continue, by providing a rapid local release of an anti-restenotic drug and avoiding prolonged drug/polymer interaction with the vessel wall.

To test this concept, the team conducted a three-arm trial involving 150 STEMI patients. After thrombus aspiration and pre-dilatation with a standard balloon, they were randomly assigned to receive a bare metal stent, or to undergo repeat dilatation with the paclitaxel-eluting DIOR balloon followed by bare metal stent placement, or receive a paclitaxel-eluting stent.

At six months, in-stent late luminal loss in the three groups was 0.74 mm, 0.64 mm and 0.21 mm (p<0.01), respectively, the investigators found.

Similarly, rates of in-stent binary restenosis were 26.2% with BMS only and 28.6% with DEB and BMS compared to 4.7% with the DES.

Rates of major adverse cardiac events reflected these figures, favoring the DES significantly, although it induced endothelial dysfunction, Dr. Stella and colleagues report.

“A possible explanation of the findings,” they suggest, “relies on the fact that the currently used DEB may have failed to (achieve) sufficient bioavailability of paclitaxel at the lesion site.”

They also note that contrary to the protocol, only 60% of the DEB group underwent pre-dilatation with a standard balloon, which would be expected to improve drug uptake from the DEB.

Overall, the authors say, “Local drug delivery with a DEB to the culprit plaque of a STEMI at the moment of highest inflammation remains an attractive treatment opportunity.” However, they conclude, “The DIOR DEB in combination with BMS failed to show angiographic superiority to BMS alone.”